nginx-rtmp-ffmpeg

An nginx-rtmp container for encoding streams with ffmpeg, and pushing to other streaming servers, e.g. twitch.tv

This is useful if you would like to offload the CPU cost of expensive video compression, allowing you to stream relatively uncompressed video at high bitrates on a fast, local network, and have a different PC encode and publish the stream to the remote server.

required environment variables

• STREAM_KEY: the stream key required by your streaming service, e.g. live_x01234567890123456789x

optional environment variables

• BITRATE: the bitrate, in Kbps, to output (ensure your internet upstream can handle this value), default 2500
• BUFSIZE: the bufsize, in Kbps, default BITRATE / 3
• RESOLUTION the resolution to output, default 1280x720
• PRESET the x264 preset to encode with, default veryfast
• PROFILE the x264 profile to use, default high
• FRAMERATE the framerate to output, default 30
• BFRAMES the number of B-Frames to use, default 3
• THREADS the number of CPU threads to use for encoding, default 0 for auto
• SCALER the x264 scaler to use, default lanczos
• RC_LOOKAHEAD the number of frames to lookahead for rate control, default FRAMERATE / 3
• INGEST the streaming service ingest server, default rtmp://live-jfk.twitch.tv/app
• STREAM_KEY_2: the stream key for a second streaming service
• INGEST_2 a second streaming service ingest server, default none

The variables you set will be assembled into the following ffmpeg arguments:

-s ${RESOLUTION} -c:v libx264 -preset ${PRESET} -profile:v ${PROFILE} -r ${FRAMERATE} -g ${FRAMERATE_2X} \
-x264-params \"bitrate=${BITRATE}:vbv_maxrate=${BITRATE}:vbv_bufsize=${BUFSIZE}:threads=${THREADS}:bframes=${BFRAMES}:rc_lookahead=${RC_LOOKAHEAD}:keyint=${FRAMERATE_2X}:min-keyint=${FRAMERATE_2X}:nal_hrd=cbr:scenecut=0:rc=cbr:force-cfr=1\" -sws_flags ${SCALER} -pix_fmt yuv420p -c:a copy -f flv -strict normal

If you prefer to customize the ffmpeg arguments, you can instead set the FFMPEG_ARGS environment variable, in which case none of the other optional environment variables will be used.

tips

You can see a list of Twitch suggested settings and ingest endpoints at stream.twitch.tv, and you can validate your configuration is proper and stable at inspector.twitch.tv.

When selecting your options, be aware that presets from veryfast and above noticeably lower picture quality. For more information about stream quality, read https://streamquality.report.

standalone examples

simplified:

docker run --rm -it -p 1935:1935 -e STREAM_KEY=live_x01234567890123456789x \
  shamelesscookie/nginx-rtmp-ffmpeg:latest

customized:

docker run --rm -it -p 1935:1935 -e STREAM_KEY=live_x01234567890123456789x -e THREADS=0 \
   -e BITRATE=2500 -e RESOLUTION=1280x720 -e PRESET=veryfast -e FRAMERATE=30 -e PROFILE=high \
   -e BFRAMES=3 -e INGEST=rtmp://live-jfk.twitch.tv/app shamelesscookie/nginx-rtmp-ffmpeg:latest

docker-compose example

version: '2'
services:
  nginx-rtmp-ffmpeg:
    container_name: nginx-rtmp-ffmpeg
    image: shamelesscookie/nginx-rtmp-ffmpeg:latest
    network_mode: host
    ports:
      - 1935
    restart: always
    environment:
      - STREAM_KEY=live_x01234567890123456789x
      - BITRATE=2500
      - BUFSIZE=833
      - RESOLUTION=1280x720
      - PRESET=veryfast
      - FRAMERATE=30
      - PROFILE=high
      - THREADS=0
      - BFRAMES=3
      - SCALER=area
      - RC_LOOKAHEAD=10
      - INGEST=rtmp://live-jfk.twitch.tv/app

source PC settings

Configure your streaming software to output to rtmp://<docker-server>:1935/livein Make sure you include your stream key in your streaming software as well, e.g. for OBS:

• File > Settings > Stream
• Stream Type: Custom Streaming Server
• URL: rtmp://<docker-server>:1935/livein, e.g. rtmp://mydockerbox:1935/livein
• Stream key: <your-stream-key>

Then use video settings that are very high in quality and low in overhead, e.g. for nVidia video cards:

• File > Settings > Output > Streaming
• Encoder: NVENC H.264
• Rate Control: CBR
• Bitrate: 50000 or 100000 or 150000 (depending on your local network)
• Keyframe Interval: 2
• Preset: High Quality
• Profile: high
• B-Frames: 0